"She asked how long Ian had been in the service, what he got up to and what he enjoyed.

"She made it very personal."

Mrs Molyneux was accompanied at the ceremony by her father-in-law James Molyneux and sons Jamie and Arron, who were dressed in their Marine Cadet uniforms.

She said: "If Ian had known about this he would have wondered what all the fuss was about.

"He was a very unassuming man, very proud of what he did - he absolutely loved his job and being on the boat - and he was a very, very brave man."

Mrs Molyneux added she would wear the medal with pride.

Donovan was jailed for at least 25 years in September 2011 for murdering Lt Cdr Molyneux and attempting to murder Lieutenant Commander Christopher Hodge, Petty Officer Christopher Brown, and Chief Petty Officer David McCoy.

Donovan fired the SA80 six times in the control room of the submarine. It is believed Donovan was on sentry duty and the shooting happened during a weapons changeover between shifts.

The shootings took place as local dignitaries, including the city council's mayor, chief executive and leader Royston Smith, were being given a tour of the submarine while it was berthed at the Eastern Docks on a five-day official visit to the Hampshire city.